What mountain to climb before K2

It sounds like you already have a good amount of experience under your belt, including some significant climbs and high-altitude peaks. However, K2 is considered one of the most challenging and dangerous peaks in the world, so it’s important to make sure you have the necessary skills and experience before attempting it. You should consider getting experience with technical climbing and steep, icy terrain, as well as experience with long-duration expeditions at high altitude. Additionally, it’s recommended to work with a qualified guide or mentor to assess your readiness and help prepare you for the challenges of K2.